Ann Coloproctol.  2017 Dec;33(6):219-226. 10.3393/ac.2017.33.6.219.

Difference in Tumor Area as a Predictor of a Pathological Complete Response for Patients With Locally Advanced Rectal Cancer

• Song JH
• Park YH
• Seo SH
• Lee A
• Kim KH
• An MS
• Bae KB
• Hong KH
• Hwang JW
• Kim JH
• Jung HS
• Ahn KJ

• KMID: 2439838
• DOI: http://doi.org/10.3393/ac.2017.33.6.219

Abstract

PURPOSE
This study was conducted to discover the clinical factors that can predict pathologically complete remission (pCR) after neoadjuvant chemoradiotherapy (CRT), so that those factors may help in deciding on a treatment program for patients with locally advanced rectal cancer.
METHODS
A total of 137 patients with locally advanced rectal cancer were retrospectively enrolled in this study, and data were collected retrospectively. The patients had undergone a total mesorectal excision after neoadjuvant CRT. Histologic response was categorized as pCR vs. non-pCR. The tumor area was defined as (tumor length) × (maximum tumor depth). The difference in tumor area was defined as pre-CRT tumor area - post-CRT tumor area. Univariate and multivariate logistic regression analyses were conducted to find the factors affecting pCR. A P-value < 0.05 was considered significant.
RESULTS
Twenty-three patients (16.8%) achieved pCR. On the univariate analysis, endoscopic tumor circumferential rate <50%, low pre-CRT T & N stage, low post-CRT T & N stage, small pretreatment tumor area, and large difference in tumor area before and after neoadjuvant CRT were predictive factors of pCR. A multivariate analysis found that only the difference in tumor area before and after neoadjuvant CRT was an independent predictor of pCR (P < 0.001).
CONCLUSION
The difference in tumor area, as determined using radiologic tools, before and after neoadjuvant CRT may be important predictor of pCR. This clinical factor may help surgeons to determine which patients who received neoadjuvant CRT for locally advanced rectal cancer should undergo surgery.

Keyword

Rectal neoplasms; Chemoradiotherapy

MeSH Terms

Chemoradiotherapy
Humans
Logistic Models
Multivariate Analysis
Polymerase Chain Reaction
Rectal Neoplasms*
Retrospective Studies
Surgeons